Fan-out mold packaging is an IC packaging technology that seeks to provide an increased number of external contacts for the IC compared to other packaging technologies. Fan-out mold packaging attaches a die to an interposer structure. The interposer structure has a larger area than the die attached thereto. The die is encapsulated by mold material that fills space above the interposer structure that otherwise would be unoccupied by the die. The increased area of the interposer structure allows more external contacts to be included than would be the case were the IC implemented using only the die without the interposer structure. The increased number of external contacts is obtained without having to increase the size of the die. Increasing die size tends to be more expensive than using the interposer structure and the added mold material.
As briefly noted, more than one die may be encapsulated in the mold material and attached to the interposer structure. In the case of a multi-die IC, The dies are spaced apart within the mold encapsulation. The spacing between the dies allows for an interposer structure of greater area to be attached to the dies, thereby providing additional space for the inclusion additional external contacts for the IC.
During manufacture and testing, ICs implemented using fan-out mold packaging technology are subjected to high levels of stress. The stress may induce warpage in the IC that may result in defects. For example, warpage may cause breakage in the metal interconnects of the interposer structure.